Absorbent paper products such as paper towels, facial tissues and other similar products are designed to include several important properties. For example, the products should have good bulk, a soft feel and should be highly absorbent. The product should also have good strength even while wet and should resist tearing. Unfortunately, it is very difficult to produce a high strength paper product that is also soft and highly absorbent. Usually, when steps are taken to increase one property of the product, other characteristics of the product are adversely affected. For instance, softness is typically increased by decreasing or reducing fiber bonding within the paper product. Inhibiting or reducing fiber bonding, however, adversely affects the strength of the paper web.
One particular process that has proved to be very successful in producing paper towels and wipers is disclosed in U.S. Pat. No. 3,879,257 to Gentile, et al., which is incorporated herein by reference in its entirety. In Gentile, et al., a process is disclosed in which a bonding material is applied in a fine, spaced apart pattern to one side of a fibrous web. The web is then adhered to a heated creping surface and creped from the surface. A bonding material is applied to the opposite side of the web and the web is similarly creped. The process disclosed in Gentile, et al. produces wiper products having exceptional bulk, outstanding softness and good absorbency. The surface regions of the web also provide excellent strength, abrasion resistance, and wipe-dry properties.
Although the process and products disclosed in Gentile, et al. have provided many advances in the art of making paper wiping products, further improvements in various aspects of paper wiping products remain desired. For example, many commercially available adhesives that may be used in the process disclosed in Gentile, et al. require that the paper product be placed on a heated creping surface prior to being creped from the surface. Further, in order for the adhesives to be subjected to a sufficient amount of heat, the paper must remain on a heated creping surface for an extended period of time requiring the creping drum to have a relatively large diameter. Thus, many conventional print bonded creping processes have high energy requirements.
In view of the above, a need exists for a print creping process that requires less energy in producing a product, such as a multi-ply paper product. In particular, it is believed that the process can be made much more economical if an adhesive can be selected that has lower temperature requirements during creping. Further, a need also exists for a single creped product that has improved properties and characteristics. For instance, a need exists for a creped product that has improved bulk characteristics in comparison to many conventional print bonded creping products.